Effect of solution treatment on the corrosion behaviour of aluminium alloy AA7150: Optimisation for corrosion resistance

Purpose: The present study compares the corrosion behaviour of overaged AA 7075 before and after equal channel angular pressing ECAP in two media, containing chlorides, in order to answer the question how grain refinement of aluminium alloys influences their corrosion properties.Design/methodology/approach: The effect of equal channel angular pressing ECAP on corrosion behaviour of aluminium alloy AA 7075 was studied in two water solutions, containing chloride ions: 1) 0.01 M Na2SO4 with addition of 0.01%Cl-, and 2) 3g/l H2O2 and 57g/l NaCl. The changes in electrochemical characteristics, provoked by grain size refinement after equal channel angular pressing ECAP, were found using potentiodynamic polarisation. Steady state potential, corrosion potential, corrosion current density; breakdown (pitting) potential of overaged and deformed by equal channel angular pressing ECAP aluminium alloy AA 7075 were measured.Findings: In the environment with lower chloride concentration equal channel angular pressing ECAP process led to increase in pitting corrosion resistance and in the medium with higher chloride concentration - to decrease in pitting corrosion resistance. That way grain refinement does not demonstrate a uni-directional influence on corrosion resistance of AA 70775.Research limitations/implications: The results suggest the possibility for development of materials having the same chemical composition but with different corrosion resistance to different environments.Originality/value: The paper presents the corrosion behaviour of ultrafine-grained aluminium alloy AA 7075 and the influence of the chloride ions concentration in the corrosion medium on this behaviour.

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Effects of solution treatment and aging on the microstructure, mechanical properties, and corrosion resistance of a β type Ti–Ta–Hf–Zr alloy

RSC Advances ◽

10.1039/c6ra28464g ◽

2017 ◽

Vol 7 (20) ◽

pp. 12309-12317 ◽

Cited By ~ 17

Author(s):

Jixing Lin ◽

Sertan Ozan ◽

Khurram Munir ◽

Kun Wang ◽

Xian Tong ◽

...

Keyword(s):

Mechanical Properties ◽

Corrosion Resistance ◽

Phase Transitions ◽

Corrosion Behaviour ◽

Solution Treatment ◽

Mechanical Properties And Corrosion ◽

Zr Alloy

A β type TTHZ alloy (Ti–40Ta–22Hf–11.7Zr) experienced various phase transitions during solution and aging treatments, and the different phases of the alloy significantly influenced its mechanical properties and corrosion behaviour.

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Investigation of corrosion behavior on plastically deformed aa 7075 t651 by shot peening process

Surface Topography Metrology and Properties ◽

10.1088/2051-672x/ac34c0 ◽

2021 ◽

Author(s):

Abeens M ◽

R Murugananthan

Keyword(s):

Electron Microscopy ◽

Corrosion Resistance ◽

Dislocation Density ◽

Aluminium Alloy ◽

Electrochemical Impedance ◽

Corrosion Behaviour ◽

X Ray ◽

Transmission Electron ◽

Aa 7075 ◽

Micro Structures

Abstract As AA 7075 T651 comprehensively is used in the marine naval vessels, the factor of corrosion performance always plays a significant role. In this work, an investigation is carried out to study the effect of corrosion behaviour of shot peened AA 7075 T651 in 3.5% solution. From the potentiodynamic polarization study, a 27.72% decrease is ascertained in the Icorr in shot peened specimen in correlation to unpeened aluminium alloy. A drop in Icorr from 1.883 to 1.480 mA/cm2 in shot peened specimen, indicates enhanced pitting corrosion resistance. An electrochemical impedance spectroscopy reveals a surge in the oxide layer formation on the peened surface aiding the drop in corrosion rate. Resistance to pit formations and improvement in oxygen deposition in the peened specimen is observed availing a Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray analysis (EDX). The micro structures of the peened and unpeened specimen are captured using optical microscopy and Transmission electron microscopy (TEM). Micro-strain, dislocation density is also calculated from the X- ray diffraction analysis (XRD), in which grain size reduces by 28.07%, dislocation density surges by 38.65% and micro strain increases by 21.95% in peened specimen in correlation to unpeened AA 7075 T651, resulting in a surge in corrosion resistance by 27.92% in the peened specimen in correlation to unpeened aluminium alloy.

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Improvement in the microhardness and corrosion behaviour of Ti-14Mn biomedical alloy by cold working

Materials Research Express ◽

10.1088/2053-1591/ac4b77 ◽

2022 ◽

Author(s):

Mohammed Gouda ◽

Salah Salman ◽

Saad Ebied

Keyword(s):

Corrosion Resistance ◽

Cold Rolling ◽

Corrosion Behaviour ◽

Cold Deformation ◽

Solution Treatment ◽

Inert Atmosphere ◽

Linear Increase ◽

Β Phase ◽

Before And After ◽

Mechanical Properties And Corrosion

Abstract β-titanium alloys are essential in many applications, particularly biomedical applications. Ti-14Mn β-type alloy was produced using an electric arc furnace from raw alloying elements in an inert atmosphere. The alloy was homogenized at 1000 °C for 8 hr to ensure the complete composition distribution, followed by solution treatment at 900 °C, then quenched in ice water. The alloy was subjected to cold deformation via cold rolling with different ratios: 10, 30, and 90%. The phases change, microstructure, mechanical properties, and corrosion resistance of Ti-14Mn alloys were evaluated before and after cold rolling. The results showed that the β-phase is the only existed phase even after a high degree of deformation. The microstructure shows a combination of twinning and slipping deformation mechanisms in the deformed alloy. Microhardness values indicated a linear increase equal to 30% by increasing the ratio of cold deformation due to the strain hardening effect. The corrosion resistance of Ti-14Mn alloy was doubled after 90% cold rolling.

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INVESTIGATION OF THE CORROSION BEHAVIOUR OF ALUMINIUM ALLOY IN SELECTED ENVIRONMENTS

Environment Technology Resources Proceedings of the International Scientific and Practical Conference ◽

10.17770/etr2019vol3.4191 ◽

2019 ◽

Vol 3 ◽

pp. 92

Author(s):

Kalina Kamarska

Keyword(s):

Corrosion Resistance ◽

Corrosion Rate ◽

Aluminium Alloy ◽

Corrosion Behaviour ◽

Chloride Ions ◽

Nitrate Ions

The corrosion behaviour of aluminium alloy EN AW-2011 was investigated in selected environments of various electrolytes using gravimetric technique. The results showed that, under the conditions employed in the present work, the corrosion rate of this alloy depends on the specific ions present in solution. The corrosion resistance of aluminium alloy EN AW-2011 is higher in solutions of acids and salts containing sulfate and nitrate ions than in these consisting chloride ions.

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Corrosion Behaviour of a Laser-MIG hybrid welding-brazing Joint of 6061 Aluminium Alloy to SUS304 Stainless Steel

CORROSION ◽

10.5006/3866 ◽

2021 ◽

Author(s):

ruilin liu ◽

Yunqi Liu ◽

Zheng Lei ◽

Hui Tang ◽

Shaoxiong He ◽

...

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

Weld Metal ◽

Aluminium Alloy ◽

Electrochemical Impedance ◽

Corrosion Behaviour ◽

Salt Spray ◽

Chemical Properties ◽

Open Circuit ◽

Hybrid Welding

Lightweight steel-aluminium structures have broad application prospects because of their lowering weight characteristics, however, the corrosion of welding-brazing joints in steel-aluminium structures is less concerned or studied. In this paper, the corrosion behaviour of the Laser-MIG hybrid welding-brazing joints of steel-aluminium is investigated through the tests and analysis of salt spray, immersion and electrochemistry. The salt spray and immersion tests show that obvious galvanic corrosion occurs at the welded joints, in which the aluminium side is seriously corroded while the steel side is not corroded. The OCP values of the aluminium alloy and the weld metal are similar (approximately -0.48 V), and the stainless steel has a higher OCP value of -0.33 V. The corrosion resistance of the weld metal is lower than aluminium- as well as steel-base materials. The corrosion resistance of the joints is controlled by the aluminium alloy part of the two metals based on the open-circuit potential and EIS analysis. A possible corrosion process schematic for the physical/chemical properties of a welding-brazing joint immersed in a sodium chloride solution is proposed according to electrochemical impedance spectroscopy.

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The Effect of Heat Treatment and Welding Parameters on the Corrosion Behaviour of a Friction Stir Welded 6056 Aluminium Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.38.285 ◽

2008 ◽

Vol 38 ◽

pp. 285-297

Author(s):

T. Monetta ◽

M. Montuori ◽

Antonio Squillace ◽

Francesco Bellucci

Keyword(s):

Heat Treatment ◽

Corrosion Resistance ◽

Thermal Treatment ◽

Aluminium Alloy ◽

Intergranular Corrosion ◽

Corrosion Behaviour ◽

Welding Parameters ◽

Thermal Treatments ◽

Friction Stir ◽

Parent Alloy

The current research has assessed the correlation between welding parameters and corrosion behaviour for friction stir welded 6056 aluminium alloy. Different thermal treatments and welding parameters were considered. For the welding parameters studied in this project, the data strongly indicate that sensitivity to corrosion is linked to the welding parameters employed. Substantial differences were found for the higher and lower speed welding parameters, with the lower speed parameters appearantly resulting in less corrosion resistance. The most widespread form of corrosion observed was pitting; however, intergranular corrosion (IGC) was also seen. While the T78 thermal treatment appears to decrease the corrosion resistance of the parent alloy, the weld region tends to improve, with the nugget being cathodic.

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Effect of the Microstructure and Environmental Exposure Conditions on the Corrosion Behaviour of the 2050 Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.794-796.205 ◽

2014 ◽

Vol 794-796 ◽

pp. 205-210 ◽

Cited By ~ 1

Author(s):

Mathilde Guérin ◽

Eric Andrieu ◽

Grégory Odemer ◽

Joël Alexis ◽

Christine Blanc

Keyword(s):

Corrosion Resistance ◽

Diffraction Analysis ◽

Aluminium Alloy ◽

Environmental Exposure ◽

Intergranular Corrosion ◽

Corrosion Behaviour ◽

Electron Backscattered Diffraction ◽

Service Conditions ◽

Exposure Conditions

Alternate immersion-emersion tests were performed for a 2050 aluminium alloy to characterize its corrosion resistance with exposure conditions representative of in service-conditions. Tests were performed for T34 samples and aged samples. After continuous immersion tests, T34 samples exhibited intergranular corrosion while intragranular corrosion was observed for aged samples. The alternate immersion-emersion tests led to a corrosion extension to the subgrain boundaries, for both T34 and aged samples, as shown by electron backscattered diffraction analysis.

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Evaluation of Corrosion Behaviour for Aluminium Alloy 7075 in 5% NaCl Solution under Slightly Varying Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.984-985.557 ◽

2014 ◽

Vol 984-985 ◽

pp. 557-563

Author(s):

D.S. Manoj Abraham ◽

H. Kanagasabapathy ◽

Richu John ◽

Muthu Yasar ◽

Shobin Paul

Keyword(s):

Corrosion Resistance ◽

Aluminium Alloy ◽

Corrosion Behavior ◽

Low Temperatures ◽

Penetration Rate ◽

Corrosion Behaviour ◽

Nacl Solution ◽

Small Temperature ◽

Temperature Changes ◽

Logarithmic Law

The main focus of this work is to study and evaluate the corrosion behavior of aluminium alloy 7075 under slightly varying temperature conditions. The corrosion behavior was found out using the Salt Mist test. Aluminium alloy 7075 possesses better corrosion resistance, so it is important to foresee the corrosion behavior of this alloy for varied applications. The Corrosion Penetration Rate was evaluated for the small temperature changes and the results show that the penetration rate increases as temperature increases gradually along with the time for which the specimens are tested. The final result is that aluminium alloy 7075 follows logarithmic law of corrosion at low temperatures.

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